The invention relates to a method for identifying a short circuit to the positive terminal of a battery in an electrical circuit of a motor vehicle having an electronic power switch that can be actuated by a control device and having at least one electrically operated switch, preferably a plurality of electrically operated switches, that switch(es) on and off loads, the switched state of said switches being reported to the control device and it being concluded that the operation is then fault-free when the connected loads are supplied with voltage when the electronic power switch is switched on and a “short circuit” or “load drop” message is produced at the switches that switch on and off loads when the electronic power switch is switched off.
Objects of the present invention are also a circuit device that comprises an electronic module and is embodied in such a manner as to be suitable for carrying out the method, and also a computer program and a computer program product that are likewise suitable for carrying out the method.
Modern vehicles are provided in the control device with electronic power switches in engine control devices, which switches switch on and off the battery voltage of one or a plurality of loads. These switches are electronic switches and perform substantially the function of an electronic master relay. However, they are encumbered with the problem that it is not possible using these electronic switches to identify a short circuit to the positive terminal of a battery at the output of the power switch. The object of the invention is therefore to provide a method that renders it possible to identify a short circuit to the positive terminal of a battery at the output of the power switch in a manner that is simple to perform.